In semi-conductor components, especially memory components, for instance DRAMs (DRAM=Dynamic Random Access Memory and/or dynamic read/write memory) a voltage level VINT used inside the component can differ from a voltage level used outside the component, e.g., from a voltage level (supply voltage level) VDD, e.g., made available to the semi-conductor component from an external voltage source.
The internally used voltage level VINT can be lower than the level VDD of the supply voltage—for instance the internally used voltage level VINT can amount to 1.5 V and the supply voltage level VDD for instance to between 1.5 V and 2.5 V, etc.
An internal voltage level VINT that has been reduced in relation to the supply voltage level VDD is such that power losses inside the semi-conductor component can be reduced.
In addition, the voltage level VDD of the external voltage supply can be subject to relatively strong fluctuations.
The supply voltage is therefore—in order to allow the component to be operated in a fault-free manner and/or as reliably as possible—usually converted by means of a voltage regulator into an internal voltage VINT (subject to only to relatively minor fluctuations and regulated to a particular constant reduced value).
Conventional voltage regulators (e.g., corresponding down converter regulators) may for instance include a differential amplifier and a p field-effect transistor. The gate of the field-effect transistor can be connected with an output of the differential amplifier, and the source of the field-effect transistor for instance with the external voltage supply.
A reference voltage VREF—subject only to relatively minor fluctuations—is applied to the plus and/or minus input of the differential amplifier. The voltage emitted at the drain of the field effect transistor can be directly back connected with the minus input of the differential amplifier, or with a voltage divider inter-connected.
The differential amplifier regulates the voltage present at the gate connection of the field effect transistor in such a way that the (back-connected) drain voltage—and thereby the voltage emitted by the voltage regulator—remains constant and as high as the reference voltage, or for instance higher by a particular factor.
For generating the above reference voltage VREF, a corresponding conventional reference voltage generator device, for instance a band gap reference voltage generator can be used, which generates—for instance by means of one or more diodes—a signal exhibiting a constant voltage level VBGR from the above supply voltage exhibiting the above relatively high supply voltage level VDD (which may at times be subject be to relatively strong voltage fluctuations).
The signal exhibiting the constant voltage level VBGR can be relayed to a buffer circuit, correspondingly retained (buffered) there and further distributed in the form of corresponding signals exhibiting the above reference voltage level VREF (for instance to the above voltage regulator (and/or to the plus and/or minus input of the corresponding voltage regulator differential amplifier) and/or to further devices, provided on the semi-conductor component, for instance further voltage regulators).
For these and other reasons, there is a need for the present invention.